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arXiv · 2004.14229

Complexity Analysis of a Fast Directional Matrix-Vector Multiplication

Günther Of·Raphael Watschinger
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Abstract

We consider a fast, data-sparse directional method to realize matrix-vector products related to point evaluations of the Helmholtz kernel. The method is based on a hierarchical partitioning of the point sets and the matrix. The considered directional multi-level approximation of the Helmholtz kernel can be applied even on high-frequency levels efficiently. We provide a detailed analysis of the almost linear asymptotic complexity of the presented method. Our numerical experiments are in good agreement with the provided theory.

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Günther Of, Raphael Watschinger. 2021-01-07. Complexity Analysis of a Fast Directional Matrix-Vector Multiplication. https://doi.org/10.1007/978-3-030-67077-1_3

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